This is revised application for the second renewal of a training program designed to train pathology- oriented medical scientists grounded in molecular, pathobiologic, and clinical aspects of cancer. This Program has three major aims: 1) to train MD or MD/PhD scientists (particularly pathologists) for careers in cancer research at academic institutions or in industry;2) to train PhD scientists - at the post-doctoral and pre-doctoral levels - to understand morphological and clinical, as well as mechanistic, aspects of cancer while preparing them for investigative careers;and 3) to recruit and train highly qualified minority trainees for productive careers in a field in which they are currently underrepresented. The Training Program has made significant achievements in each of these areas. For example, twenty of twenty nine post-doctoral trainees supported during the first two funding periods (10 years) now have faculty positions at the rank of Instructor or higher, three have positions .as Research Associate or equivalent, four have undertaken further training, and only two have positions not directly reflecting their training in this Program. Additional progress in the training of PhD scientists has been made with initiation of a Neoplasia Tract in the Pathobiology Graduate Program, beginning with the most recent funding period. With support from this training grant, highly qualified graduate students, committed to careers in cancer research, have been recruited to the Training Program. Finally, the Program has been successful in achieving goals of third major aim, to train highly qualified minority trainees for careers in cancer research and related fields. During the past funding period, 3 African American and 2 Hispanic trainees have been sponsored (including 2 trainees who entered the program in the most recent year of funding). Thus, this Training Program has assumed a critical role in the overall educational duties of Johns Hopkins and of the cancer research field. The cancer research field continues to have needs for qualified MD (or MD/PhD) pathologists, for PhD scientists trained to understand the pathological basis of disease, and for well-trained scientists from minority groups. For these reasons, this Program seeks a renewal of funding for pre-doctoral and post- doctoral trainees in the Pathobiology of Cancer. With a committed faculty and an outstanding cancer research environment, this Program is positioned for continued success in this important training mission.